Hi The Disk Defragmenter that comes with Windows 7 Home Premium 32 bits shows that my hard disk is 1% fragmented. It remains 1% no matter how many times I run the defragmenter. ANy idea what this can be ? Tnanks

It is possible some system files that cannot be defragmented got fragmented. It also is possible some large file cannot be entirely defragmented due to available disk space. after all you need to have contiguous free diskspace of at least the filesize to be able to defragment the file. My recommendation on this is not to bother. Such a small amount of fragmentattion will not be a performance issue. In general, Windows 7 handles defragmentation more than fine without any user intervention. However, there are third party defragmentation tools available which will succeed in defragmenting the last % too. Question still is whether your effort on finding and runnign the tool is not just a waste of time! MCP/MCSA/MCTS/MCITP

Hi SenneVL, thanks for answering so fast to my question. The hard disk is actually a data disk and does afaik not contain system files (Windows is on another hard disk on my system). It is a 500 GB drive of which only 10 GB is used. There are no extremely large file on the disk. That is why the 1% fragmentation bothers me (I cannot understand why it can't be defragged).

Ignore it. 1% or 0% doesn't make a difference: Disk Defragmentation – Background and Engineering the Windows 7"A programmer is just a tool which converts caffeine into code" CLIP- Stellvertreter http://www.winvistaside.de/

Some limitations are detailed in wikipedia: http://en.wikipedia.org/wiki/Disk_Defragmenter_%28Windows%29

The Engineers who built the Defrag system said themselves that they decided to make the defragger basically "give up" at a certain point, because trying too much will (a) wear out the hard drive and (b) not gain any performance, so why bother. Read the details in their own words here: http://blogs.msdn.com/b/e7/archive/2009/01/25/disk-defragmentation-background-and-engineering-the-windows-7-improvements.aspx If this was helpful, please vote by clicking the green triangle. If it solves the issue, click Propose as Answer. Thanks!

I read somewhere the difference after defrag is negligible. File permissions may be stoping the proccess.

Recycle Bin on that drive probably contains the data that will not be defragged. Use Disk Cleanup on that drive to show its recycle bin.